The present invention relates to contoured, plastic shell chairs. Plastic shell chairs are popular because of the attractive contours which can be molded into the exterior supporting shell. The plastic not only fulfills the structural requirements of the chair, but also provides an attractive exterior surface. Generally, the shells are somewhat difficult to upholster since the contours which are usually designed into such shells are extremely difficult to cover with upholstery.
Chairs having upholstered exteriors employ simple, boxy straight lines and an upholstering envelope. The envelope includes seams along the sharp contour lines which generally exist between the back and the arms and the seat, arms and back. In fact, most manufacturers do not even attempt to upholster the bottom surface of the chair. It would be very difficult to sew an upholstery envelope for a chair having a contoured, as opposed to a straight line appearance.
Some attempt to overcome this difficulty by designing chairs with very straight backs and with separate arms. The back and the arms are upholstered separately and then joined together. However, no effort is made to upholster the bottom of the chair. Further, this approach has the drawback of enabling one to design a chair having only a conventional, box-like appearance, rather than a striking, contoured appearance. Yet, another problem with such chairs is that the means for interconnecting the arms to the rest of the chair are generally clumsy. Indeed, chairs having separate exterior shell components suffer from the fact that the edges of the joined components are left exposed and visible. In each cases, a special trim piece must be used.
Another problem encountered in the manufacture of contoured plastic shell chairs is one relating to the manner in which cushions are to be supported in the shell. The shell does not provide any framework to which such cushions can readily be attached. Gluing is sometimes utilized, but this is a time consuming operation in view of the need to carefully locate each of the separate cushions as it is adhered to the shell.
These related problems tend to restrict the chair designer, both in giving the chair the contoured lines which he desires and in selecting the plastic material from which the contoured shell is to be made.